21127191 has 8 divisors (see below), whose sum is σ = 28327680. Its totient is φ = 14005752.

The previous prime is 21127159. The next prime is 21127193. The reversal of 21127191 is 19172112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21127191 - 2⁵ = 21127159 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21127193) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19135 + ... + 20208.

It is an arithmetic number, because the mean of its divisors is an integer number (3540960).

Almost surely, 2^21127191 is an apocalyptic number.

21127191 is a deficient number, since it is larger than the sum of its proper divisors (7200489).

21127191 is a wasteful number, since it uses less digits than its factorization.

21127191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39525.

The product of its digits is 252, while the sum is 24.

The square root of 21127191 is about 4596.4324209108. The cubic root of 21127191 is about 276.4482973915.

The spelling of 21127191 in words is "twenty-one million, one hundred twenty-seven thousand, one hundred ninety-one".